Abstract:In order to select excellent clones of Eucalyptus urophylla, the growth and leaf characters of 20 clones in half-year-old under water and nutrient stresses were analyzed and evaluated by using a randomized complete block design according two factors and three levels. The results showed that leaf apex angle (LBA), leaf length (LL), leaf width (LW), leaf perimeter (LP) and leaf area (LA) had significant differences among water and nutrient treatments, indicated that water and nutrient had influence on the leaf size. There were significant positive correlations between most of growth and leaf characters, and a few showed significantly negative correlations. The principal components analysis showed that the cumulative contribution rate of the first four principal components accounted for 98%, indicating that they had strong representativeness. Growth traits under water, nutrient, water×nutrient interaction reached a significant level except for ground diameter (GD) under water × nutrient interaction. The component variance for H, GD and CW ranged from 2.19 to 149.59, and repeatability ranged from 0.16 to 0.45. The four excellent clones, such as LDUA10, ZQUA9, ZQUA8 and LDUA24, were selected according to 20% selected ratio and genotypic value, and the H, GD and CW of four clones was 5.0%, 12.8% and 14.5% higher than control, which would provide basis for further selection and extension of superior clones.
